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Two-Photon Absorption and the Cyclotron Line in Her X-1

Published online by Cambridge University Press:  25 April 2016

D. B. Melrose
Affiliation:
Department of Theoretical Physics, University of Sydney
A. J. Parle
Affiliation:
Department of Theoretical Physics, University of Sydney

Extract

The cyclotron line in Her X-1 is a hard X-ray feature at ≈ 58 keV discovered by Trümper et al. (1977). A cyclotron emission line at about this energy had been predicted by Gnedin and Sunyaev (1974) and Basko and Sunyaev (1975). They developed a model for the infall of accreted matter onto a magnetized neutron star’s surface, and concluded that hot spots would form at the polar caps and radiate X-rays. They predicted that the optional depth for bremsstrahlung would be less than unity, that for Compton scattering greater than unity and that for cyclotron absorption much greater than unity. A cyclotron line is then implied due to the emission spectrum lying below the black-body spectrum except near the cyclotron energy where it rises up to the black-body limit. More recent developments of these background ideas have been reviewed by Börner (1980).

Type
Contributions
Copyright
Copyright © Astronomical Society of Australia 1981

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References

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